Campaigns routinely haggle over the details of the debates, right down to the temperature of the studio, but every major party candidate in modern times has ultimately agreed to participate.

It would be unprecedented for Trump to skip a general election debate.

It would also be risky. Voters consistently tell pollsters that the debates help them decide which candidate to support.

Trump’s primary complaint in his tweet was that two of the debates are scheduled on the same nights as NFL games.

That’s true — but it was also true in 2012. Sporting events, religious holidays, and other factors cause scheduling headaches every four years.

The first debate of 2016, slated for September 26, coincides with “Monday Night Football” on ESPN.

The vice presidential debate is scheduled one week later on October 4, a Tuesday.

The second presidential debate, on October 9, coincides with “Sunday Night Football” on NBC.

The final debate is slated for October 19, a Wednesday.

NFL games are played on Sundays, Mondays and Thursdays in the fall. Fridays and Saturdays are effectively ruled out because TV viewing is lower on weekend evenings. That only leaves Tuesdays and Wednesdays.

One complication was Yom Kippur on Tuesday, October 11 and Wednesday, October 12.

Trump’s tweet also brought up Bernie Sanders, saying “same as last time w/ Bernie,” a veiled reference to the Democratic primary debate calendar. Many critics believed that the Democratic National Committee sought to minimize the debate schedule, thereby favoring Clinton over Sanders.

The Commission on Presidential Debates has many critics too, but it was specifically formed to provide a nonpartisan structure for debates that doesn’t favor one candidate over another.

The parties are not involved in the debate scheduling, a point that Spicer made on CNN: The commission “announces the dates without consultation of the parties or the candidates.”

He acknowledged that the dates were set last September, before the primaries even began, but said that “doesn’t mean it’s a good system.”

“You look at the debates being on major NFL nights and you wonder why people are upset about that? This was a dumb idea and should be revisited,” Spicer said, throwing the RNC’s support behind Trump’s complaint.

When Trump tweeted on Friday night, New York Times political correspondent and CNN analyst Maggie Haberman responded, “Is this a prelude to not doing all three?”

Another interpretation is that Trump wants to make sure he has the biggest possible audience for the debates.

Before Trump weighed in, former Obama speechwriter Jon Favreau asserted on Friday’s “Keepin’ It 1600” podcast that Clinton should call for more debate sessions.

If Trump “says no, then he looks weak, which is against brand,” Favreau theorized.

His podcast co-host Dan Pfeiffer, a former Obama aide and CNN commentator, brought up the ongoing guessing game about whether Trump will participate.

“The rumor is that Trump may not agree to the debates. He is not engaged” in the normal negotiations between the campaigns and the commission, Pfeiffer said.